220 BRITISH MARINE ALG. 
tufts of this little plant are from 2in. to 8in. long, and are densely 
branched ; the lesser branches being more or less pinnated or branchedina 
similar manner, the ramuli being subulate or awl-shaped, and of nearly 
uniform length, but shortened towards the tips of the pinnules, and | 
sometimes curved outwards or reflexed. Favelle are usually clustered, 
and are placed about the centre of the stems of the plumules, as re- 
presented at d, Fig. 201. The colour of this pretty summer annual is a 
rose or purplish-red. It is met with at Brighton and in Torbay, but in 
much greater abundance and beauty at Plymouth, where, on muddy 
rocks at low-water mark, I have often detected its little rosy fronds just 
appearing on the surface of its uninviting habitat. C. Borreri, dedicated 
to Mr. Borrer, of Brighton, is a beautiful and very distinctly-marked 
species, all the upper branches being set with distichous plumules 
(or plumed branchlets set in alternate opposite series), the lower portions 
being destitute of ramuli, the upper furnished with wide-spreading pinne, 
the lowest of whichare longest. These little closely-plumed branches give 
a beautifully-feathered outline to the plant, and, under the microscope, 
when this species is in tetrasporic fruit, the ramuli of the little feather- — 
like branchlets seem as though they were bordered with crimson cherries. 
The favellz also are a beautiful sight, being seated in pairs on each side of 
_ the stem of a plumule; each lobe being contained within a transparent 
envelope, as represented at e, Fig. 201. The colour varies froma pale rose. 
red to a dull brown-red. The filaments are also of variable length, 
being from two inches to five inches long. The plant is in perfection in 
May or June, and is taken in various parts of England and Ireland. My 
finest specimens were gathered on the muddy banks near Tor Point, and 
under Mount Edgcumbe in Plymouth Harbour. C. tripinnatum is an 
extremely rare and veryexquisite little annual. Under the microscope it has 
very much the character of the foregoing; but it differs from that, as 
from all others of its tribe, in having a very minute ramulus, which springs 
from the first joint in the angle of each plumule. It has been taken on the 
west coast of Ireland and at Plymouth, but hitherto I have not had the 
good fortune of meeting with it. C.affine, another very rare species, quite 
unknown to me, except through Dr. Harvey’s beautiful figure of it in the 
“ Phycologia Britannica,’’ was found many yearsago on the shores of the 
Isle of Bute. OC. fasciculatum is also very rare, and, like the foregoing 
plant, is, to my mind, a very doubtful species. It was found many years 
agoat Yarmouth by Mr. Borrer. The figure of it in the Phycologia is that 
of an exceedingly beautiful plant, but any lengthened description here of 
such very decided rarities seems to me to be utterly unnecessary. C. gracil- 
limum (Fig. 202) is probably the most graceful and beautiful of all the 
British species of this charming tribe of alge. It was discovered, I believe, 
by Mrs. Griffiths, on the muddy base of the pier at Torquay. The plant was 
published originally under its present name, by Professor Agardh; but it 
is to be regretted that the name C. filicinum, proposed for it by its 
discoverer. was not adopted in the first instance, since the plant .is so 
